diff --git a/CSU/1120.cpp b/CSU/1120.cpp
new file mode 100644
index 0000000..238022c
--- /dev/null
+++ b/CSU/1120.cpp
@@ -0,0 +1,58 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cstring>
+
+#include <vector>
+#include <algorithm>
+using namespace std;
+
+namespace LCIS_INT_LESSMEM
+{
+    const int MAXL=1024;
+    int ldp[MAXL];
+    int deal(int* pa,int na,int *pb,int nb)
+    {
+        memset(ldp,0,MAXL*sizeof(int));
+        for(int i=1;i<=na;i++)
+        {
+            int k=0;
+            for(int j=1;j<=nb;j++)
+            {
+                if(pa[i]>pb[j]) k=max(k,ldp[j]);
+                else if(pa[i]==pb[j])
+                {
+                    ldp[j]=k+1;
+                }
+            }
+        }
+        int ans = 0;
+        for(int i = 1; i <= nb; i++) ans = max(ans, ldp[i]);
+        return ans;
+    }
+}
+
+/// CSUOJ 1120
+int a[1024];
+int b[1024];
+int main()
+{
+    int t;
+    scanf("%d",&t);
+    while(t--)
+    {
+        int na;
+        scanf("%d",&na);
+        for(int i=1;i<=na;i++)
+        {
+            scanf("%d",&a[i]);
+        }
+        int nb;
+        scanf("%d",&nb);
+        for(int i=1;i<=nb;i++)
+        {
+            scanf("%d",&b[i]);
+        }
+        printf("%d\n",LCIS_INT_LESSMEM::deal(a,na,b,nb));
+    }
+    return 0;
+}